Free UUID Generator Online — v1, v4 & v7
Generate, validate, and decode UUIDs instantly with our free online tool. Supporting UUID v1 (timestamp), v4 (random), and v7 (time-ordered) with bulk generation, validation, and ready-to-use code snippets for 10+ programming languages.
UUID Versions Explained
| Version | Method | Sortable | Best For |
|---|---|---|---|
| UUID v1 | Timestamp + MAC | Yes | Legacy systems |
| UUID v4 | Random | No | General purpose |
| UUID v7 | Timestamp + Random | Yes | Database primary keys |
Features
- Generate — Create single or bulk UUIDs in v1, v4, or v7 format
- Validate — Check if a string is a valid UUID and identify its version
- Decode — Extract timestamp and other metadata from v1 and v7 UUIDs
- Code Snippets — Copy UUID generation code for Python, JavaScript, TypeScript, Go, Java, C#, PHP, Ruby, Rust, Swift, and more
- Bulk Generation — Generate up to 1,000 UUIDs at once
Frequently Asked Questions
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier that is unique across space and time. UUIDs are used to identify database records, API resources, sessions, and more without requiring a central authority.
What is the difference between UUID v1, v4, and v7?
UUID v1 uses timestamp and MAC address (time-ordered but exposes hardware info). UUID v4 is completely random and the most widely used. UUID v7 combines a Unix timestamp with random data for time-ordered IDs that are database-index friendly.
Which UUID version should I use?
Use v4 for general-purpose unique IDs. Use v7 for database primary keys where time-ordering improves index performance. Avoid v1 for new projects due to MAC address privacy concerns.
Is a UUID the same as a GUID?
Yes. GUID is the term used in Microsoft technologies, while UUID is the standard from RFC 4122. Both refer to the same 128-bit identifier format.
Can two UUIDs ever be the same?
The probability of a UUID v4 collision is about 1 in 5.3 x 10^36. You would need to generate 2.71 quintillion UUIDs for a 50% chance of a single collision. In practice, UUIDs are treated as guaranteed unique.